The oil pump is a light and compact pump, an oil pump with a housing made of aluminum-containing material and movable molded parts arranged in the housing is proposed;
whereby the The movable shape is made at least in part from a sinterable iron-based alloy material containing at least one austenite, and wherein a sinterable shape is made from a material having a coefficient of thermal expansion that is at least 60% of the coefficient of thermal expansion of the housing.
Oil pump mechanical principle
The oil suction and pressure of the fuel injection pump is achieved by the reciprocating movement of the piston in the piston sleeve. When the piston is in the down position, the two oil holes on the piston sleeve are opened, the inner chamber of the piston sleeve communicates with the oil passage in the pump body, and the fuel fills the oil chamber quickly.
When the cam hits the roller of the reel body, the plunger is lifted. Move up from the beginning of the piston until the oil hole is blocked by the top end face of the piston. During this time, the fuel is pushed out of the oil chamber by the movement of the piston and flows into the oil gallery. Therefore, this portion of the lift is called the prestroke.
When the piston blocks the oil hole, the oil pressure process begins. When the piston moves up, the oil pressure in the oil chamber increases sharply.
When the pressure exceeds the oil relief valve spring force and the upper oil pressure, the oil relief valve opens and the fuel is pushed into the oil line and sent to the injector.
The moment when the oil inlet hole on the piston sleeve is completely blocked by the top end surface of the piston is called the theoretical starting point of oil supply. If the KAs the piston moves further up, the oil supply continues and the oil pressure process continues until the spiral bevel on the piston leaves the piston sleeve and returns to the oil bore. When the oil hole is opened, the high-pressure oil flows through the oil chamber. The longitudinal groove on the piston and the oil return hole on the piston sleeve flow back to the oil gallery in the pump body.
At this time, the oil pressure in the oil chamber of the piston sleeve drops rapidly, the oil outlet valve falls back on the valve seat under the action of the spring, and the oil pressure is high-pressure oil line, and the injector stops immediately to inject oil. Although the piston continues to move up at this point, the oil supply has stopped.
The moment when the oil return hole on the piston sleeve is opened by the hypotenuse of the piston is called the theoretical end of oil supply. In the whole process of the piston moving up, only the middle TPart of the stroke is the oil pressure process, and this stroke is called the effective stroke of the piston.
Fuel Quantity Adjustment
In order to meet the demands of the diesel engine load, the fuel injection pump fuel supply must be sufficient zero when the fuel supply (full load) in the range the fuel supply is stopped (stop). The fuel supply is adjusted by rotating all the pistons of the fuel injection pump simultaneously via the gear rod and the rotary sleeve.
When the piston rotates, the oil supply start time remains unchanged, while the oil supply end time changes due to the change in the position of the oil return hole of the piston sleeve in the hypotenuse of the piston. As the piston rotates at different angles, the effective stroke of the piston is also different, so the amount of oil supplied will also change accordingly.
The larger the angle at which thePiston rotates at non-supply stage 1, the greater the distance from the top of the piston to the hypotenuse of the oil return hole of the piston sleeve, the greater the oil supply. Small.
When the diesel engine stops, the oil must be shut off. To do this, the longitudinal groove on the piston can be turned so that it is opposite the oil return hole on the piston sleeve. At this time, throughout the piston stroke, the fuel in the piston sleeve flows back to the oil gallery through the longitudinal groove and the oil return hole, and there is no oil pressure process, so the fuel supply is zero.
As the piston rotates, the oil delivery amount is adjusted by changing the timing of the end point of the oil delivery amount. This method is referred to as the oil delivery end point adjustment method.
The oil supply volume of the oil pump should meet the needs of the diesel engine under different working conditions. With the sameFeed angle should also ensure the oil supply duration The same, and the oil supply should be started quickly, and the oil supply should be stopped quickly and neatly to avoid oil dripping.
Depending on the shape of the combustion chamber and the way the mixture is formed, the fuel pump must deliver the fuel to the injector with sufficient pressure to ensure good atomization quality.
Oil pump installation instructions
1. The quality of the pump installation has a very important influence on the smooth operation and life of the pump. Therefore, the installation correction work must be carefully and not be carried out hastily.
2. The installation height, length and pipe diameter of the pump suction pipe should correspond to the calculated value, be short and reduce unnecessary losses (such as bends, etc.); and Make sure that when the pump is running, the permissibleliquid NPSH value is not exceeded.
3. The suction and discharge lines should have brackets. The pump must not bear the load of the pipeline.
4. The location where the pump is installed should be large enough to facilitate maintenance work.